Young boy undergoing an Electroencephalograph (EEG) examination, showing the numerous electrodes attached to his head & face. The EEG records the electrical activity from different parts of the brain for a process known as Brain Electrical Activity Mapping (BEAM), whereby a computer maps an image of the brain in response to external visual or auditory stimuli, making a comparison with EEG data from a normal control subject. The final image produced is a colour map of statistical variance from the make-up of a normal brain, which is of use in the diagnosis of sensory defects (eg impaired hearing) in young children.